Gyroplane to Bensen Type B8MV Design, St. Mary's, NSW, 27 December 1970

The pilot, who was not licenced, did not ensure that the design, construction and maintenance of the aircraft, and the manner in which it was operated, met standards which provided an adequate margin of safety.

The pilot had never received any formal flying training. He did not hold a pilot licence and it is probable that he did not meet the medical standards laid down for the holders of such licences. He had flown gyro craft over a period of 4 years and on the day of the accident he was flying a self built, unregistered, unapproved aircraft of the type within the close environs of the airstrip. His own sets of rotor blades were unserviceable and he had fitted a borrowed set of wooden blades which he had not previously used. The performance characteristics of this set varied from his own blades and were significantly different to a set of borrowed metal blades he had used exclusively for some months before the accident. He flew for 30 minutes on a series of brief flights, adjusting the tracking of the borrowed blades and when he was satisfied that they were tracking accurately, he took off and then made a low run along the airstrip. The aircraft then climbed to a height of about 70 feet, turned to the left through some 250 degrees and straightened when it was headed obliquely towards the centre of the strip. The manoeuvres were controlled, were made at a slow speed and were consistent with the flying habits of the pilot. Soon after the turn was completed there was a noise similar to an engine backfire, a puff of smoke or vapour appeared and the craft entered a steep nose down descent. The descent angle was reduced, but recovery was not effected before the aircraft impacted heavily on an upslope.